DIY Neuro-Motor Experiments, Part 2

One thing I want to dispel immediately is that this is about normal "handedness". Sure, you can pick up a ball and throw it with your non-dominant hand/arm and experience the sensation of a "chicken-arm", but that's not the point under investigation. No, this has more to do with skills that are shared unevenly across the body (or even directionally on a side). Consequently, the attempt at a mirror image action produces sub-par performance in both the dominant and non-dominant sides. Secondly, we expect that repetition of an action will lead to better performance of that action, so repeated performance of the mirror image motion will eventually produce smoother and more efficient motion. This, in turn, raises a few questions: What does it feel like for an expert to be suddenly "thrown backward in time", performing at the same level as an intermediate of beginner? How long does it take to master the mirror movement and how does the process compare to the original learning? Is this experience in any way comparable to what someone with a mild stroke experiences? Further, does this new learning impact former skills, and if so, positively or negatively?

Allow me to go back some 20-plus years and explain my mirror-image writing experiments. The idea was to print backwards (perfect mirror image) using my dominant hand. As you might guess, initially this was a mess. It required considerable concentration and I often wrote some letters backwards (i.e. in the normal fashion). After a week or so of practicing for about 30 minutes per day, I became relatively at ease and the required concentration dropped. I still made occasional blunders though, specifically, the letter 's' and transposing 'b' and 'd'. After a couple of weeks I was getting pretty good but then I noticed something strange: I would sometimes write letters backwards when writing in the normal fashion (you guessed it, I started transposing 'b' and 'd' and similar sorts of things). Needless to say, this was a strong impetus to stop the experiment as my job requires a lot of writing.

Jump ahead to the present. New drummers first focus on learning rudiments on the snare drum. These are basic sticking patterns. For example, there's the five stroke single roll which goes right-left-right-left-right and then left-right-left-right-left. In shorthand: RLRLR LRLRL. You tend to learn these in symmetrical pairs. A double stroke roll would be written like this: RRLLRRLL and so on. One of the first interesting rudiments a drummer learns is the paradiddle: RLRR LRLL. You can hear new drummers practicing this pattern over and over and over trying to get it ever smoother, ever faster, and ever effortless. Always symmetrical and always on the snare drum directly in front of them. Then they move on to the double paradiddle RLRLRR LRLRLL (and I must admit that I typed that as a paradiddle but screwed it up the first time because the L key is to the right of the R key), and other variations. The fun comes when you start applying these rudiments to the drum kit and here's my major point: Due to the layout of the standard kit there is a tendency to prefer certain sticking patterns because they "work well" with the position of the body relative to the drums. For example, a clockwise (descending pitch) fill is easier to do if you start with the right stick as the right stick "leads the action". The average drummer never worries about the reverse because the kit is not arranged in such a way as allow moving from the snare in a counter-clockwise direction and that leads to a certain asymmetry of skill.

OK, so as I mentioned in part one, I have a symmetrical kit, so I began to notice some of these things. I began to purposely execute a fill counter-clockwise identical to the one I just did clockwise. Some of it was pretty messy. Then, a few weeks ago, I began to rework some of my rudiments in a "traveling" mode, that is, playing the rudiments across several drums in sequence instead of sticking to the central snare drum. Now I had done this many years ago, but without a symmetric layout at the time, I wasn't "traveling" both ways (more "to" than "fro"). I began by working single paradiddles across the toms to the left and right in various ways, for example, keeping the single strokes on the snare and moving the double strokes to the toms or vice versa. I tried the same thing with double and triple paradiddles. I was getting better. Then something odd happened: I reached back into memory and tried what I call a paradiddle-diddle (I don't know if this is the real name, it's just something I made up many years ago as an exercise). It goes RLRRLLRR LRLLRRLL. Halfway through one cycle I had to stop. I couldn't do it. Somehow, all of this "symmetrical traveling" screwed up my paradiddle-diddle (and for some reason, that sentence sounds oddly pornographic). It wasn't like I had forgotten it; it's one of those little thingies I rip off almost reflexively, but with my focus on this new material, I hadn't exercised that particular firing pattern in weeks. Perhaps it somehow got co-opted, just like my 'b' and 'd' of 20 years ago. After a little practice though, it came back, and eventually I'll add it to the traveling repertoire.

Another interesting thing happened, and that's that my feet seem better able to make intertwined patterns. I currently play double kick pedals and I plan on picking up a second hi-hat pedal to make a symmetrical foot layout. This will require a little electronic surgery on the part of the hi-hat pedals to get them to function properly, but it's a simple enough sacrifice for science (and if the patient dies on the table I can always call Roland for another force sensing resistor for four bucks).

I feel as though I have only scratched the surface of possibilities with this and I'll share some of my mental and physical sensations of "re-learning" and associated thoughts down the road. I remain interested in any experiments or similar experiences you wish to share.

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Another fun thing to do is to start in different parts of the rudiment. I used to have an annoying habit of accentuating the first note of a given rudiment (i.e., Rlrr Lrll...), and it made for some pretty monotonous fills. At first I sought to compensate by moving the downbeat to another part of the grouping (i.e., rrLr llRl, rLrl lRlr, etc.).

Since then, I've gotten much better at evening everything out, but I nevertheless find that my aforementioned efforts increased my repertoire dramatically.

One of the skills of a carpenter, and many other trades, is the use of a hammer. It occurred to me today that I have, over the years, made considerable progress in using one with my non-dominant hand. It's not something I took much notice of, since there are not a lot of occasions demanding it. But sometimes it is unavoidable. For a long time this was an inconvenient, and potentially damaging practice, though when I did use my sinister hand today (under a bathroom vanity) I immediately thought of your neuro-motor experiment.

For a long time taking the hammer in the "wrong" hand produced a sensation somewhat like trying to walk straight after being spun around until dizzy; that is, a disorienting and mildly disturbing sensation. Sort of like learning to ice skate or casting a fly for the first time. Not unpleasant but trying. Uncomfortable would be a good way to express it.

I certainly can't brag that I can drive a nail with as little attention lefty as I do righty, but it struck me today that I can do it well enough to actually talk to someone at the same time.

I have discovered that controling the tool off-handedly is best achieved by limiting the muscle groups involved. With my right hand I can use hand, wrist, arm, shoulder, back, chest, and leg muscles to deliver a killer blow. With the left I seem to limit the muscles to those from the shoulder down, more often just hand and wrist. I'll be paying attention in the future to see if I can incorporate more muscles and achieve an acceptable degree of accuracy. (Actually I'll be looking for excuses to do so, now that you bring it up.)

I don't know anything about playing the drums outside the fact that I have never been able to cause a musical instrument to do anything but complain, but it seems obvious that correctly manipulating a drumstick is quite similar to using a hammer or other striking tool. The amount of feedback involved in guiding the business end to its target with just the right speed and force seems to be huge. Somehow practice (muscle memory?) reduces the need to consciously monitor the whole data stream to merely checking a few critical data points.

Thanks for the suggestions in your posts; I might never have thought of what it is that I do when I pound away. Ain't science wonderful?

By Crudely Wrott (not verified) on 12 Feb 2007 #permalink

Are there any things that you do that require both hands simultaneously, each doing a very distinct and somewhat involved motion? Reversing those is what I'm finding most interesting. I mean, I expect leftie to feel spastic doing rightie's job, but if it's a two-handed operation, how does rightie feel doing leftie's job? When drumming, I find that the reverse motions are accompanied by a tightness across the chest and arms. I feel as though I am fighting myself and nothing is fluid or relaxed. After repeated practice bouts, it's almost as if my brain says "yes, I can do this" and shuts up about complaining. Kind of like an over-protective mother just letting her kid go out and play. The interesting thing is that sometimes the break-over is rather sudden. It's not always a linear progression of gradually getting better.

Here's something, Jim, driving a screw. This could be with a traditional screw driver or a corded or battery-operated screw gun or drill. The hand that holds the tool is responsible for aligning the tool with the screw and providing enough force to engage the screw in the material as well as to keep the drive bit engaged in the head of the screw. The hand that holds the screw is responsible for the proper orientation of the screw in space (pointy end down) and providing steadiness as the thread begins to bite. In my case, the right hand wields the tool and the left the screw and all is well.

When called upon to reverse hand position and task, my reaction is like you described when doing the same while drumming. There is a sense of muscular (and mental) conflict, a tension in the muscles controlling the actions and an angst at losing control (your lack of fluidity).

In the case at hand, eh-erm, my right hand normally does the brute force part of the task while the left does the fine tuning. I press hard on the tool with my right while adjusting the orientation of the screw with my left. Since making the tool work correctly requires strength and steadiness, more muscle groups are involved and they are exerting lots of force. Aligning the screw is a task that requires tactile sensitivity and frequent subtle adjustment.

When I reverse positions I am calling on my right hand muscles to be sensitive and rapid in response time, a task for which they have become unsuited. And my left hand muscles are not used to applying a strong, consistent force. As a result I must perform each incremental part of the task with much more conscious effort. While driving a screw in my preferred way happens almost automatically, the opposite case involves much deliberate effort and as a result takes more time.

If I had to drive roughly half the screws left handed I imagine that they would go in as easily as the ones driven righty. The thing is I will go to great lengths to find a way to do it in the fashion to which I am accustomed. To the extent of turning by whole body in any axis necessary to allow me to apply my right hand to the tool and my left to the screw. While this is not always possible it is worth the effort in terms of accuracy. It's very embarrassing to slip off the head of the screw and mar a finished surface (or a finger). In some cases this is not a concern but for the most part I try not to leave tool marks on my work in any case.

What intrigues me about this is that learning to reverse hands is like learning for the first time with the advantage of already knowing the basics; just backasswards.

Is there a known mechanism in the brain that could be accountable for such an inversion? That is, flipping the world left to right, up to down or front to back. I'm curious because your posts have got me thinking about how to take advantage of such an ability for the sake of efficiency and accuracy. A guy does take pride in his work.

By Crudely Wrott (not verified) on 13 Feb 2007 #permalink